1. Field of the Invention
The present invention relates to a filter for smoking.
2. Description of the Related Art
For removing the harmful substances from tobacco smoke, it has been proposed to add various adsorbents and modifiers to filters for cigarettes.
However, since the components having a high boiling point, e.g., benzo[a]pyrene, exhibits behavior equal to that of particles, it was difficult to remove selectively the components having a high boiling point by using the conventional tobacco filter.
Japanese Patent Disclosure No. 60-110333, for example, discloses a tobacco filter made of acetate fiber carrying granular blue-green alga Spirulina. It is reported in this prior art that a tobacco smoke was passed through a pipe provided with a filter carrying the blue-green alga Spirulina so as to determine the adsorption removal rate relative to the filter that did not carry the blue-green alga Spirulina. The removal rates are 42.4% for nicotine, 53.2% for tar, and 75.1% for 3,4-benzopyrene.
On the other hand, Japanese Patent Disclosure No. 62-79766 proposes a tobacco filter prepared by rolling a sheet carrier carrying floc of Fomes annosus/Ganoderma lucidum mixture or powder/floc of Coriolus versicolor. It is reported that the removal rate of 3,4-benzopyrene was 62% and 35% for the respective filters.
However, the conventional tobacco filters exemplified above are incapable of sufficiently removing the high boiling point components from the tobacco smoke.